Guido et Ginevra, ou La Peste de Florence (French: Guido and Ginevra, or the Plague at Florence) is a grand opera in five acts by Fromental Halévy to a libretto by Eugène Scribe.

It was translated into Italian and performed in three acts by the Théâtre-Italien at the Salle Ventadour beginning on 17 February 1870.

The opera contains touches of the composer's innovative orchestration, with a mélophone in Act II, and with Ginevra's tomb scene set to dark woodwind and brass instruments using diminished seventh harmonies.

Scribe drew the elements of his plot from the history of Florence by Louis-Charles Delécluze The Medici court Ginevra is to be married to the Duke of Ferrara.

During the ceremony, a poisoned veil she has been given causes her to faint away in a deathlike trance; the sculptor Guido mourns her.